Sun Exposure Behaviors and Vitamin D Status in Healthy Adults

Background: Vitamin D status is highly associated with behavioral factors such as sun exposure patterns. The present study aimed to determine sun exposure behaviors and vitamin D status among healthy adults in Shiraz, Iran.Methods: In this cross-sectional study, 201 healthy individuals aged 20-40 years were randomly selected from different areas of Shiraz, Iran. Demographic characteristics, vitamin D intake through diet or supplements, and sun exposure habits were assessed and also serum 25-hydroxyvitamin D (25(OH)D) concentration was measured.Results: The mean concentration of serum 25(OH)D was 21.43±9.2 ng/mL. There were no significant associations between 25(OH)D level and sun exposure habits except wearing long-sleeve shirts (p=0.010). However, in the participants who did not take vitamin D supplements, serum 25(OH)D level had a negative association with sunscreen use(p=0.045), frequent use of sunscreen (p=0.045), and wearing long-sleeve shirts (p=0.023), and positive correlation with duration (p=0.045) and time of sun exposure (p=0.026) and the percentage of body surface area exposed to the sun (r=0.245, p=0.010).Conclusion: Vitamin D deficiency is a common problem among healthy young adults in Shiraz, Iran, and sun exposure habits can affect vitamin D status only among the participants who did not take vitamin D supplements.